Tire Size Calculator

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Stock Sizes

  • 255/75-16

Plus Sizes

  • 255/75-16

Accepts P-Metric and Inches
/ R
/ R
135/80r12 vs 155/70r13 Tire Comparison Side By Side
  135/80-12 155/70-13 Difference
Diameter inches (mm) 20.5 (520.8) 21.54 (547.2) 1.04 (26.4) 5.1%
Width inches (mm) 5.31 (135) 6.1 (155) 0.79 (20) 14.8%
Circum. inches (mm) 64.42 (1636.14) 67.68 (1719.08) 3.27 (82.94) 5.1%
Sidewall Height inches (mm) 4.25 (108) 4.27 (108.5) 0.02 (0.5) 0.5%
Revolutions per mile (km) 983.62 (611.19) 936.17 (581.71) -47.46 (-29.49) -4.8%

Speedometer Difference

Speedo Reading Actual Speed
20 mph (32.19 km/h)21.01 mph (33.82 km/h)
25 mph (40.23 km/h)26.27 mph (42.27 km/h)
30 mph (48.28 km/h)31.52 mph (50.73 km/h)
35 mph (56.33 km/h)36.77 mph (59.18 km/h)
40 mph (64.37 km/h)42.03 mph (67.64 km/h)
45 mph (72.42 km/h)47.28 mph (76.09 km/h)
50 mph (80.47 km/h)52.53 mph (84.55 km/h)
55 mph (88.51 km/h)57.79 mph (93 km/h)
60 mph (96.56 km/h)63.04 mph (101.46 km/h)
65 mph (104.61 km/h)68.29 mph (109.91 km/h)
70 mph (112.65 km/h)73.55 mph (118.36 km/h)
75 mph (120.7 km/h)78.8 mph (126.82 km/h)
80 mph (128.75 km/h)84.06 mph (135.27 km/h)
85 mph (136.79 km/h)89.31 mph (143.73 km/h)
90 mph (144.84 km/h)94.56 mph (152.18 km/h)
95 mph (152.89 km/h)99.82 mph (160.64 km/h)
100 mph (160.93 km/h)105.07 mph (169.09 km/h)

Gear Ratio / RPMs for New Tire (@ 65 mph)
2.35 2.73 2.94 3.07 3.21 3.31 3.42 3.55 3.73 3.91 4.11 4.27 4.56 4.88 5.13 5.29 5.38 5.71 6.17 7.17
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
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